Pseudomonas fluorescens is a widespread spoilage bacterium in food,and its spoilage characteristics and biofilm formation are regulated by N-acyl-homoserine lactone(AHLs)quorum sensing(QS)system.Quorum quenching(QQ)is...Pseudomonas fluorescens is a widespread spoilage bacterium in food,and its spoilage characteristics and biofilm formation are regulated by N-acyl-homoserine lactone(AHLs)quorum sensing(QS)system.Quorum quenching(QQ)is considered as an effective strategy to control the spoilage bacteria.Therefore,this study revealed a new QQ bacteria Lactiplantibacillus plantarumYP4-1-2.Notably,the crude cell extract(CCE)from L.plantarum YP4-1-2 showed strongly QQ activity against the AHLs of P.fluorescens.The degradation rate of AHLs(N-octanoyl-L-homoserine lactone)reached 25.90%,78.57%and 100%at theCCE protein concentrations of 57,86 and 114 g/mL,respectively.In addition,the CCE could drastically reduce the formation of biofilm,bacterial motility(swimming and swarming),and the release of extracellular protease and biogenic amines of P.fluorescens.Real-time polymerase chain reaction(PCR)results revealed that the CCE downregulated QS-related genes(rhlI,rhlR,aprX,algA,orm,flgA,and ldcA).Finally,using whole-genome sequencing analysis,the active substance in the CCE was identified to be penicillin V acylase(PVA)and named LpPVA.Meanwhile,homologous modeling and molecular docking analysis showed that the binding effect of LpPVA on long-chain AHLs was better than that on short-chain AHLs.This study demonstrated that L.plantarum YP4-1-2 could be considered as a promising QS inhibitor and antibiofilm agent against foodborne spoilage bacteria.展开更多
基金supported by the Open Foundation of Oceanology Research Institute of Bohai University(BDHYYJY2020002).
文摘Pseudomonas fluorescens is a widespread spoilage bacterium in food,and its spoilage characteristics and biofilm formation are regulated by N-acyl-homoserine lactone(AHLs)quorum sensing(QS)system.Quorum quenching(QQ)is considered as an effective strategy to control the spoilage bacteria.Therefore,this study revealed a new QQ bacteria Lactiplantibacillus plantarumYP4-1-2.Notably,the crude cell extract(CCE)from L.plantarum YP4-1-2 showed strongly QQ activity against the AHLs of P.fluorescens.The degradation rate of AHLs(N-octanoyl-L-homoserine lactone)reached 25.90%,78.57%and 100%at theCCE protein concentrations of 57,86 and 114 g/mL,respectively.In addition,the CCE could drastically reduce the formation of biofilm,bacterial motility(swimming and swarming),and the release of extracellular protease and biogenic amines of P.fluorescens.Real-time polymerase chain reaction(PCR)results revealed that the CCE downregulated QS-related genes(rhlI,rhlR,aprX,algA,orm,flgA,and ldcA).Finally,using whole-genome sequencing analysis,the active substance in the CCE was identified to be penicillin V acylase(PVA)and named LpPVA.Meanwhile,homologous modeling and molecular docking analysis showed that the binding effect of LpPVA on long-chain AHLs was better than that on short-chain AHLs.This study demonstrated that L.plantarum YP4-1-2 could be considered as a promising QS inhibitor and antibiofilm agent against foodborne spoilage bacteria.
